Problem: If $x \diamond y = x-8y$ and $x \star y = 2x-3$, find $(-6 \star 5) \diamond 1$.
Explanation: First, find $-6 \star 5$ $ -6 \star 5 = (2)(-6)-3$ $ \hphantom{-6 \star 5} = -15$ Now, find $-15 \diamond 1$ $ -15 \diamond 1 = -15-(8)(1)$ $ \hphantom{-15 \diamond 1} = -23$.